Optimizing Search Engine Coverage of a WordPress Blog

To opti­mize the search engine cov­er­age a robots.txt file placed in the root of the HTML serv­er can exclude some paths of the web­site from being indexed by the Google crawler.

In Word­Press this file can be gen­er­at­ed auto­mat­i­cal­ly. In the case of using Nginx a redi­rec­tion rule has to be imple­ment­ed in the nginx con­fig file so that the query to robots.txt is redi­rect­ed to the Word­Press index.php file.

# generate robots.txt with wordpress
location = /robots.txt {
    try_files     $uri $uri/ /index.php?$args;
    access_log    off;
    log_not_found off;

Now Word­Press is used to gen­er­ate the robots.txt file which is dynam­i­cal­ly edit­ed by plu­g­ins and themes.

Raspberry Pi on the Go

Some­times you are on the go and would like to play around with your Rasp­ber­ry Pi. I am using a quite easy set­up with my Mac­Book Air.


To pow­er the RPi I am using a stan­dard USB‑A to micro USB cable con­nect­ed to one of the USB ports on the note­book. It is strong enough to pow­er the RPi.

Console Access

One pos­si­bil­i­ty would be to get a stan­dard USB to ser­i­al inter­face, oper­at­ing at 3.3 V and hook it up to the UARTs of the RPi to get a ser­i­al con­sole. This is one per­fect solu­tion as long as you do not want to use the RPi’s UART for some­thing else. Then you need to recon­fig­ure two oth­er pins, etc.

I am using a dif­fer­ent approach: I a using a thun­der­bolt to eth­er­net adapter and con­nect the RPi to the mac with a short net­work­ing cable. As the net­work is con­fig­ured to use DHCP I need to start a DHCP serv­er on the mac. The eas­i­est way is to use inter­net shar­ing in macOS. Just enable it in pref­er­ences and take a look at the ifcon­fig in the ter­mi­nal to get the router’s IPv4 address. Usu­al­ly the RPi has the same net­work but the last octet is 2. Mean­ing when the mac has the IP adress the RPi would have Then just use plain SSH to con­nect to the RPi.

Converting videos from iPhone for PowerPoint 2010

I had the prob­lem of how to prop­er­ly embed a video into Pow­er­Point 2010 run­ning on Win­dows 7. I used the insert video com­mand but a nor­mal h264 video from my iPhone with a .mov exten­sion did not work. So the video had to be con­vert­ed into a dif­fer­ent format.

If you ever want­ed to con­vert video, there is an almost omnipo­tent tool ffm­peg, which can do the job. And also in this case the solu­tion was to con­vert the file into some ancient wma codec using the fol­low­ing ffm­peg command:

ffmpeg -i InFile.mov  -q:v 9 -c:v wmv2 -c:a wmav2 -async 1 -b:a 256k OutFile.avi

The .avi file gen­er­at­ed this way can be insert­ed eas­i­ly into Pow­er­Point 2010 and will be embed­ded into the pre­sen­ta­tion. On the slide the video can be con­fig­ured to play auto­mat­i­cal­ly when the slide appears or after being clicked.

Monitoring a Fritz!Box using RRDtool

RRD­tool is a pop­u­lar and ver­sa­tile pro­gram to store and aggre­gate time-depen­dent data in way that the size need­ed for stor­age is not grow­ing indef­i­nite­ly. Fur­ther­more it has a pow­er­ful plot­ting engine to gen­er­ate nice graphs. It is there­fore wide­ly used to mon­i­tor net­work devices.

The pop­u­lar Fritz!Box router can be queried using the TR-064 pro­to­col for the num­ber of trans­ferred bytes. The Fritz Speed pack­age brings these two togeth­er to enable mon­i­tor­ing and graph­ing the WAN traf­fic of the Fritz!Box.

Check the project on GitHub or direct­ly go to the docs.

CarPlay nachgerüstet — Ein Erfahrungsbericht

Meine Voraussetzungen

Ich fahre einen Mer­cedes CLK Bau­jahr 2003 und dieser hat ein ein­fach­es Navi ver­baut, welch­es so direkt keine Möglichkeit­en zum Anschließen eines Tele­fons über Blue­tooth oder zumin­d­est Aux hat. So war die Idee, man müsste mal das Radio tauschen und glück­licher­weise ist in der Mit­telkon­sole ein Dop­pel-DIN Schacht ver­baut, den man doch mit entsprechen­den Adaptern nutzen kön­nen sollte.

Gesagt, getan, deshalb nun eine Recherche im Inter­net, um rauszufind­en wie man das Radio ein­baut und natür­lich welch­es Radio es sein soll. Da das Auto nicht mehr soo frisch ist, war klar dass das Bud­get nun begren­zt ist und ich ein möglichst gün­stiges Mod­ell mit Apple CarPlay Unter­stützung haben wollte.

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New Beefy Storage Home Server — Part 1

The Aim

After using my com­put­ing equip­ment for some time my desk got filled with 3 exter­nal hard dri­ves con­tain­ing back­ups and archived data such as videos, pho­tos. Even worse these dri­ves spin down after a while result­ing in a 6 sec­ond lag when open­ing a file open or save pan­el. Fur­ther­more the use of a HFS+ filesys­tem for long-time stor­age seemed not very attrac­tive to me as it can get cor­rupt­ed silently.

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Simple Samba Configuration for Public Shares

The Aim

Some­times it is nec­es­sary to share files from a POSIX oper­at­ing sys­tem (Lin­ux, FreeB­SD, etc.) with Win­dows com­put­ers via the net­work. For this task Sam­ba is the pow­er­ful inter­op­er­abil­i­ty suite which can han­dle this task. To dis­tin­guish between these two sys­tems I will dif­fer­en­ti­ate between POSIX (that is the sam­ba serv­er) and Win­dows computers.

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